Accelerated and intensified manufacturing of an adenovirus-vectored vaccine to enable rapid outbreak response.

The Coalition for Epidemic Preparedness Innovations' "100-day moonshot" aspires to launch a new vaccine within 100 days of pathogen identification, followed by large-scale vaccine availability within the "second hundred days." Here, we describe work to optimize adenoviral vector manufacturing for rapid response, by minimizing time to clinical trial and first large-scale supply, and maximizing output from the available manufacturing footprint. We describe a rapid virus seed expansion workflow that allows vaccine release to clinical trials within 60 days of antigen sequence identification, followed by vaccine release from globally distributed sites within a further 40 days. We also describe a perfusion-based upstream production process, designed to maximize output while retaining simplicity and suitability for existing manufacturing facilities. This improves upstream volumetric productivity of ChAdOx1 nCoV-19 by approximately fourfold and remains compatible with the existing downstream process, yielding drug substance sufficient for 10,000 doses from each liter of bioreactor capacity. This accelerated manufacturing process, along with other advantages such as thermal stability, supports the ongoing value of adenovirus-vectored vaccines as a rapidly adaptable and deployable platform for emergency response.

The neural stem cell line CTX0E03 promotes behavioral recovery and endogenous neurogenesis after experimental stroke in a dose-dependent fashion.

BACKGROUND: This study investigated behavioral recovery in rats following implanting increasing doses of CTX0E03 cells into the putamen ipsilateral to the stroke damage. Postmortem histological analysis investigated possible mechanisms of behavioral recovery. METHODS: . At 4 weeks after middle cerebral artery occlusion (MCAO), rats were treated with 4500, 45,000, or 450,000 CTX0E03 cells or vehicle implanted into the putamen with testing on a battery of tasks preocclusion and postocclusion. Histological examination of brains included assessment of lesion volumes, implant cell survival and differentiation, changes to host brain matrix, angiogenesis, and neurogenesis using immunohistochemical methods. RESULTS: . Statistically significant dose-related recovery in sensorimotor function deficits (bilateral asymmetry test [BAT; P < .0002] in the mid- and high-dose groups and rotameter test after amphetamine exposure [P < .05] in the high-dose group) was found in the CTX0E03 cell implanted groups compared to the vehicle group. In-life functional improvements correlated with cell dose, though did not correlate with survival of CTX0E03 cells measured at postmortem. Surviving CTX0E03 cells differentiated into oligodendroglial and endothelial phenotypes. MCAO-induced reduction of neurogenesis in the subventricular zone (SVZ) was partially restored to that observed in sham operated controls. No adverse CTX0E03 cell-related effects were observed during in-life observations or on tissue histology. CONCLUSIONS: . This study found that the implantation of CTX0E03 human neural stem cells in rats after MCAO stroke promoted significant behavioral recovery depending on cell dose. The authors propose a paracrine trophic mechanism, which is triggered early after CTX0E03 cell implantation, and which in turn targets restoration of neurogenesis in the SVZ of MCAO rats.

Methodological study investigating long term laser Doppler measured cerebral blood flow changes in a permanently occluded rat stroke model.

Cerebral blood flow is impaired during middle cerebral artery occlusion in the rat model of stroke. However, the long term effects on cerebral blood flow following occlusion have received little attention. We examined cerebral blood flow in both sides at multiple time points following middle cerebral artery occlusion of the rat. The bilateral cerebral blood flow in young male Sprague Dawley rats was measured at the time of occlusion, as well as 4, 10 and 16 weeks after occlusion. Under the present experimental conditions, the difference between the left and right side's cerebral blood flow was observed to appear to switch in direction in a visual oscillatory fashion over time in the sham-treated group, whereas the occluded animals consistently showed left side dominance. One group of rats was intraparenchymally transplanted with a human neural stem cell line (CTX0E03 cells) known to have benefit in stroke models. Cerebral blood flow in the lesioned side of the cell-treated group was observed to be improved compared to the untreated rats and to demonstrate a similar oscillatory nature as that observed in sham-treated animals. These findings suggest that multiple bilateral monitoring of cerebral blood flow over time can show effects of stem cell transplantation efficiently as well as functional tests in an animal stroke model.